title: Salt-responsive ERF1 regulates reactive oxygen species-dependent signaling during the initial response to salt stress in rice.
abstract: Early detection of salt stress is vital for plant survival and growth. Still, the molecular processes controlling early salt stress perception and signaling are not fully understood. Here, we identified salt-responsive ERF1 (SERF1), a rice (Oryza sativa) transcription factor (TF) gene that shows a root-specific induction upon salt and hydrogen peroxide (H2O2) treatment. Loss of SERF1 impairs the salt-inducible expression of genes encoding members of a mitogen-activated protein kinase (MAPK) cascade and salt tolerance-mediating TFs. Furthermore, we show that SERF1-dependent genes are H2O2 responsive and demonstrate that SERF1 binds to the promoters of MAPK kinase kinase6 (MAP3K6), MAPK5, dehydration-responsive element bindinG2A (DREB2A), and zinc finger protein179 (ZFP179) in vitro and in vivo. SERF1 also directly induces its own gene expression. In addition, SERF1 is a phosphorylation target of MAPK5, resulting in enhanced transcriptional activity of SERF1 toward its direct target genes. In agreement, plants deficient for SERF1 are more sensitive to salt stress compared with the wild type, while constitutive overexpression of SERF1 improves salinity tolerance. We propose that SERF1 amplifies the reactive oxygen species-activated MAPK cascade signal during the initial phase of salt stress and translates the salt-induced signal into an appropriate expressional response resulting in salt tolerance.
authors.affiliation: Institute of Biochemistry and Biology, University of Potsdam, 14476 Potsdam, Germany.
authors.forename: Romy
authors.initials: R
authors.lastname: Schmidt
authors.forename: Delphine
authors.initials: D
authors.lastname: Mieulet
authors.forename: Hans-Michael
authors.initials: HM
authors.lastname: Hubberten
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Obata
authors.forename: Rainer
authors.initials: R
authors.lastname: Hoefgen
authors.forename: Alisdair R
authors.initials: AR
authors.lastname: Fernie
authors.forename: Joachim
authors.initials: J
authors.lastname: Fisahn
authors.forename: Blanca
authors.initials: B
authors.lastname: San Segundo
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Guiderdoni
authors.forename: Jos H M
authors.initials: JH
authors.lastname: Schippers
authors.forename: Bernd
authors.initials: B
authors.lastname: Mueller-Roeber
mesh_terms: D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D055785:Gene Knockdown Techniques; D006861:Hydrogen Peroxide / Q000494:pharmacology; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D020930:MAP Kinase Kinase Kinases / Q000235:genetics / Q000378:metabolism; D018613:Microscopy, Confocal; D008957:Models, Genetic; D008969:Molecular Sequence Data; D009154:Mutation; D012275:Oryza / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D016877:Oxidants / Q000494:pharmacology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding; D017382:Reactive Oxygen Species / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D055049:Salt Tolerance / Q000235:genetics; D015398:Signal Transduction / Q000187:drug effects*; D012965:Sodium Chloride / Q000494:pharmacology*; D013312:Stress, Physiological / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D008164:Luminescent Proteins; D016877:Oxidants; D010940:Plant Proteins; D017382:Reactive Oxygen Species; D014157:Transcription Factors; D012965:Sodium Chloride; D006861:Hydrogen Peroxide; D020930:MAP Kinase Kinase Kinases